Read the docs
TI-2023-18642 Aliases CVE-2023-36849GHSA-px74-prrr-j3jp

Junos OS and Junos OS Evolved: The l2cpd will crash when a malformed LLDP packet is received

Priority LOW 29CWE-703Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

An Improper Check or Handling of Exceptional Conditions vulnerability in the Layer-2 control protocols daemon (l2cpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker to cause a Denial of Service (DoS). When a malformed LLDP packet is received, l2cpd will crash and restart. The impact of the l2cpd crash is reinitialization of STP protocols (RSTP, MSTP or VSTP), and MVRP and ERP. Also, if any services depend on LLDP state (like PoE or VoIP device recognition), then these will also be affected. Continued receipt of such packets will lead to a sustained Denial of Service. This issue affects: Juniper Networks Junos OS 21.4 versions prior to 21.4R3-S3; 22.1 versions prior to 22.1R3-S3; 22.2 versions prior to 22.2R2-S1, 22.2R3; 22.3 versions prior to 22.3R2. Juniper Networks Junos OS Evolved 21.4-EVO versions prior to 21.4R3-S2-EVO; 22.1-EVO versions prior to 22.1R3-S3-EVO; 22.2-EVO versions prior to 22.2R2-S1-EVO, 22.2R3-EVO; 22.3-EVO versions prior to 22.3R2-EVO.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00303 23rd percentileScored 2026-11-07
Fix Fixed Junos OS (Juniper Networks): 21.4R3-S3, 22.1R3-S3, 22.2R2-S1 +2Junos OS Evolved (Juniper Networks): 21.4R3-S2-EVO, 22.1R3-S3-EVO, 22.2R2-S1-EVO +2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
JuniperJunos OS21.4 to before 21.4R3-S3; 22.1 to before 22.1R3-S3; 22.2 to before 22.2R2-S1, 22.2R3; 22.3 to before 22.3R221.4R3-S3, 22.1R3-S3, 22.2R2-S1, 22.2R3, 22.3R2Patch availableCNA
JuniperJunos OS Evolved21.4 to before 21.4R3-S2-EVO; 22.1 to before 22.1R3-S3-EVO; 22.2 to before 22.2R2-S1-EVO, 22.2R3-EVO; 22.3 to before 22.3R2-EVO21.4R3-S2-EVO, 22.1R3-S3-EVO, 22.2R2-S1-EVO, 22.2R3-EVO, 22.3R2-EVOPatch availableCNA
  • Junos OS VendorJuniper Affected 21.4 to before 21.4R3-S3; 22.1 to before 22.1R3-S3; 22.2 to before 22.2R2-S1, 22.2R3; 22.3 to before 22.3R2 Fixed in 21.4R3-S3, 22.1R3-S3, 22.2R2-S1, 22.2R3, 22.3R2 Patch available CNA
  • Junos OS Evolved VendorJuniper Affected 21.4 to before 21.4R3-S2-EVO; 22.1 to before 22.1R3-S3-EVO; 22.2 to before 22.2R2-S1-EVO, 22.2R3-EVO; 22.3 to before 22.3R2-EVO Fixed in 21.4R3-S2-EVO, 22.1R3-S3-EVO, 22.2R2-S1-EVO, 22.2R3-EVO, 22.3R2-EVO Patch available CNA

CPE configurations NVD · 49

CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:21.4:-:*:*:*:*:*:*21.4VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r1:*:*:*:*:*:*21.4 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r1-s1:*:*:*:*:*:*21.4 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r1-s2:*:*:*:*:*:*21.4 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r2:*:*:*:*:*:*21.4 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r2-s1:*:*:*:*:*:*21.4 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r2-s2:*:*:*:*:*:*21.4 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r3:*:*:*:*:*:*21.4 r3VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r3-s1:*:*:*:*:*:*21.4 r3-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:21.4:r3-s2:*:*:*:*:*:*21.4 r3-s2VulnerableJuniper
  • cpe:2.3:o:juniper:junos:21.4:-:*:*:*:*:*:* Versions 21.4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r1:*:*:*:*:*:* Versions 21.4 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r1-s1:*:*:*:*:*:* Versions 21.4 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r1-s2:*:*:*:*:*:* Versions 21.4 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r2:*:*:*:*:*:* Versions 21.4 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r2-s1:*:*:*:*:*:* Versions 21.4 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r2-s2:*:*:*:*:*:* Versions 21.4 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r3:*:*:*:*:*:* Versions 21.4 r3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r3-s1:*:*:*:*:*:* Versions 21.4 r3-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.4:r3-s2:*:*:*:*:*:* Versions 21.4 r3-s2 Vulnerable ·Juniper
Show 39 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:22.1:r1:*:*:*:*:*:*22.1 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:22.1:r1-s1:*:*:*:*:*:*22.1 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:22.1:r1-s2:*:*:*:*:*:*22.1 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:22.1:r2:*:*:*:*:*:*22.1 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:22.1:r2-s1:*:*:*:*:*:*22.1 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:22.1:r2-s2:*:*:*:*:*:*22.1 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:22.1:r3:*:*:*:*:*:*22.1 r3VulnerableJuniper
cpe:2.3:o:juniper:junos:22.1:r3-s1:*:*:*:*:*:*22.1 r3-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:22.1:r3-s2:*:*:*:*:*:*22.1 r3-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:22.2:r1:*:*:*:*:*:*22.2 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:22.2:r1-s1:*:*:*:*:*:*22.2 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:22.2:r1-s2:*:*:*:*:*:*22.2 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:22.2:r2:*:*:*:*:*:*22.2 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:22.3:r1:*:*:*:*:*:*22.3 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:22.3:r1-s1:*:*:*:*:*:*22.3 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:22.3:r1-s2:*:*:*:*:*:*22.3 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:-:*:*:*:*:*:*21.4VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r1:*:*:*:*:*:*21.4 r1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r1-s1:*:*:*:*:*:*21.4 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r1-s2:*:*:*:*:*:*21.4 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r2:*:*:*:*:*:*21.4 r2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r2-s1:*:*:*:*:*:*21.4 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r2-s2:*:*:*:*:*:*21.4 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r3:*:*:*:*:*:*21.4 r3VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:21.4:r3-s1:*:*:*:*:*:*21.4 r3-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.1:r1:*:*:*:*:*:*22.1 r1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.1:r1-s1:*:*:*:*:*:*22.1 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.1:r1-s2:*:*:*:*:*:*22.1 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.1:r2:*:*:*:*:*:*22.1 r2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.1:r2-s1:*:*:*:*:*:*22.1 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.1:r3:*:*:*:*:*:*22.1 r3VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.1:r3-s1:*:*:*:*:*:*22.1 r3-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.1:r3-s2:*:*:*:*:*:*22.1 r3-s2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.2:r1:*:*:*:*:*:*22.2 r1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.2:r1-s1:*:*:*:*:*:*22.2 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.2:r2:*:*:*:*:*:*22.2 r2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.3:r1:*:*:*:*:*:*22.3 r1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.3:r1-s1:*:*:*:*:*:*22.3 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:22.3:r1-s2:*:*:*:*:*:*22.3 r1-s2VulnerableJuniper
  • cpe:2.3:o:juniper:junos:22.1:r1:*:*:*:*:*:* Versions 22.1 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.1:r1-s1:*:*:*:*:*:* Versions 22.1 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.1:r1-s2:*:*:*:*:*:* Versions 22.1 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.1:r2:*:*:*:*:*:* Versions 22.1 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.1:r2-s1:*:*:*:*:*:* Versions 22.1 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.1:r2-s2:*:*:*:*:*:* Versions 22.1 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.1:r3:*:*:*:*:*:* Versions 22.1 r3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.1:r3-s1:*:*:*:*:*:* Versions 22.1 r3-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.1:r3-s2:*:*:*:*:*:* Versions 22.1 r3-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.2:r1:*:*:*:*:*:* Versions 22.2 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.2:r1-s1:*:*:*:*:*:* Versions 22.2 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.2:r1-s2:*:*:*:*:*:* Versions 22.2 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.2:r2:*:*:*:*:*:* Versions 22.2 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.3:r1:*:*:*:*:*:* Versions 22.3 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.3:r1-s1:*:*:*:*:*:* Versions 22.3 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:22.3:r1-s2:*:*:*:*:*:* Versions 22.3 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:-:*:*:*:*:*:* Versions 21.4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r1:*:*:*:*:*:* Versions 21.4 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r1-s1:*:*:*:*:*:* Versions 21.4 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r1-s2:*:*:*:*:*:* Versions 21.4 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r2:*:*:*:*:*:* Versions 21.4 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r2-s1:*:*:*:*:*:* Versions 21.4 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r2-s2:*:*:*:*:*:* Versions 21.4 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r3:*:*:*:*:*:* Versions 21.4 r3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:21.4:r3-s1:*:*:*:*:*:* Versions 21.4 r3-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.1:r1:*:*:*:*:*:* Versions 22.1 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.1:r1-s1:*:*:*:*:*:* Versions 22.1 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.1:r1-s2:*:*:*:*:*:* Versions 22.1 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.1:r2:*:*:*:*:*:* Versions 22.1 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.1:r2-s1:*:*:*:*:*:* Versions 22.1 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.1:r3:*:*:*:*:*:* Versions 22.1 r3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.1:r3-s1:*:*:*:*:*:* Versions 22.1 r3-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.1:r3-s2:*:*:*:*:*:* Versions 22.1 r3-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.2:r1:*:*:*:*:*:* Versions 22.2 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.2:r1-s1:*:*:*:*:*:* Versions 22.2 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.2:r2:*:*:*:*:*:* Versions 22.2 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.3:r1:*:*:*:*:*:* Versions 22.3 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.3:r1-s1:*:*:*:*:*:* Versions 22.3 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:22.3:r1-s2:*:*:*:*:*:* Versions 22.3 r1-s2 Vulnerable ·Juniper

Remediation

  • Fix · CNA Junos OS (Juniper Networks) Fixed in 21.4R3-S3, 22.1R3-S3, 22.2R2-S1, 22.2R3, 22.3R2
  • Fix · CNA Junos OS Evolved (Juniper Networks) Fixed in 21.4R3-S2-EVO, 22.1R3-S3-EVO, 22.2R2-S1-EVO, 22.2R3-EVO, 22.3R2-EVO

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-36849
  2. 2026-10-03 Alias added: GHSA-px74-prrr-j3jp

References

Advisory 1

  • TI-2023-18638 Junos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to… KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-01585 Out of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) services KEVCVSS 3.1CRITICAL 9.8
  • TI-2015-04610 Assertion failure in ISC BIND named via TKEY queries KEVCVSS 3.1HIGH 7.5
  • TI-2025-15550 Junos OS: An local attacker with shell access can execute arbitrary code KEVCVSS 4.0MEDIUM 6.7
  • TI-2023-18644 Junos OS: SRX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload and download arbitrary files KEVCVSS 3.1MEDIUM 5.3
  • TI-2023-18640 Junos OS: EX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary files KEVCVSS 3.1MEDIUM 5.3
See all 792 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences